Retirement Plans (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended | |
Dec. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Oct. 01, 2016 |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | | 100.00% | | | |
Defined Benefit Plan, Actual Plan Asset Allocations | | 100.00% | | | |
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year | | $ 900 | | | |
Defined Benefit Plan, Benefit Obligation | $ 13,728 | 14,130 | $ 13,728 | | $ 14,689 |
Defined Benefit Plan, Interest Cost | 131 | 536 | | | |
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) | (205) | 940 | | | |
Defined Benefit Plan, Benefits Paid (Deprecated 2017-01-31) | (334) | (464) | | | |
Defined Benefit Plan, Other Cost (Credit) | (553) | (610) | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 9,228 | 9,217 | 9,228 | | $ 10,228 |
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) | (113) | 813 | | | |
Defined Benefit Plan, Plan Assets, Contributions by Employer | 0 | 250 | | | |
Defined Benefit Plan, Plan Assets, Benefits Paid | (334) | (464) | | | |
Defined Benefit Plan, Funded (Unfunded) Status of Plan | (4,500) | (4,913) | (4,500) | | |
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax | $ (6) | 300 | (6) | | |
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months | | 1,890 | | | |
Defined Benefit Plan, Expected Future Benefit Payment, Year Two | | 580 | | | |
Defined Benefit Plan, Expected Future Benefit Payment, Year Three | | 610 | | | |
Defined Benefit Plan, Expected Future Benefit Payment, Year Four | | 1,580 | | | |
Defined Benefit Plan, Expected Future Benefit Payment, Year Five | | 1,290 | | | |
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter | | $ 4,060 | | | |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate | 3.85% | 4.15% | | | |
Defined Benefit Plan, Expected Return (Loss) on Plan Assets | $ (86) | $ (192) | | | |
Defined Benefit Plan, Service Cost | 0 | $ 0 | | | |
Defined contribution 401(k) plan, employer matching contribution, percent of match | | 50.00% | | | |
Defined contribution 401(k) plan, employee contributions subject to employer match (percent) | | 4.00% | | | |
401(k) plan, expense for matching contributions | | $ 4,100 | $ 3,400 | $ 3,400 | |
Defined Benefit Plan, Net Periodic Pension Benefit Cost | | | | | |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement and Curtailment | 0 | 13 | | | |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) | 45 | 357 | | | |
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax | (6) | 319 | | | |
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, after Tax | 0 | 0 | | | |
Other Comprehensive Income (Loss), Defined Benefit Plan, Settlement and Curtailment Gain (Loss), after Tax | 0 | (13) | | | |
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax | $ (6) | $ 306 | | | |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets | 6.30% | 5.80% | | | |
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate | 4.15% | 3.60% | 4.15% | | |
Liability, Defined Benefit Plan, Noncurrent | $ 4,500 | $ 4,913 | $ 4,500 | | |
Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax | 39 | 663 | | | |
Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 9,228 | 9,217 | 9,228 | | |
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 6,361 | 6,761 | 6,361 | | |
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 2,867 | 2,456 | 2,867 | | |
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 0 | $ 0 | 0 | | |
Real Assets [Member] | | | | | |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | | 8.00% | | | |
Defined Benefit Plan, Actual Plan Asset Allocations | | 5.00% | | | |
Real Assets [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 407 | $ 462 | 407 | | |
Real Assets [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 0 | 0 | 0 | | |
Real Assets [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 407 | 462 | 407 | | |
Real Assets [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 0 | $ 0 | 0 | | |
Hedge Funds, Equity [Member] | | | | | |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | | 10.00% | | | |
Defined Benefit Plan, Actual Plan Asset Allocations | | 10.00% | | | |
Hedge Funds, Equity [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 825 | $ 919 | 825 | | |
Hedge Funds, Equity [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 825 | 919 | 825 | | |
Hedge Funds, Equity [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 0 | 0 | 0 | | |
Hedge Funds, Equity [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 0 | $ 0 | 0 | | |
International Equity [Member] | | | | | |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | | 12.00% | | | |
Defined Benefit Plan, Actual Plan Asset Allocations | | 15.00% | | | |
International Equity [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 1,285 | $ 1,387 | 1,285 | | |
International Equity [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 1,054 | 1,106 | 1,054 | | |
International Equity [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 231 | 281 | 231 | | |
International Equity [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 0 | $ 0 | 0 | | |
Domestic Income [Member] | | | | | |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | | 20.00% | | | |
Defined Benefit Plan, Actual Plan Asset Allocations | | 21.00% | | | |
Domestic Income [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 1,942 | $ 1,902 | 1,942 | | |
Domestic Income [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 188 | 189 | 188 | | |
Domestic Income [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 1,754 | 1,713 | 1,754 | | |
Domestic Income [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 0 | $ 0 | 0 | | |
Fixed Income Investments [Member] | | | | | |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | | 50.00% | | | |
Defined Benefit Plan, Actual Plan Asset Allocations | | 49.00% | | | |
Fixed Income Investments [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 4,769 | $ 4,547 | 4,769 | | |
Fixed Income Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 4,294 | 4,547 | 4,294 | | |
Fixed Income Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | 475 | 0 | 475 | | |
Fixed Income Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | | | | | |
Defined Benefit Plan, Fair Value of Plan Assets | $ 0 | $ 0 | $ 0 | | |